Help using old version of Matlab Student
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
phillip
am 30 Aug. 2012
Beantwortet: Manoj Kumar
am 9 Mai 2019
Hi, I periodically use an old version 5 student edition. I'm having a rather small err large problem.
This is what happens
a=[.95 .03 .05 .97]
a =
0.9500 0.0300
0.0500 0.9700
b=a-eye(2)
b =
-0.0500 0.0300
0.0500 -0.0300
det(b)
ans =
2.7756e-018
clear
b=[-.05 .03 .05 -.03]
b =
-0.0500 0.0300
0.0500 -0.0300
det(b) ans =
0
What's happening here? Thanks.
1 Kommentar
Akzeptierte Antwort
Daniel Shub
am 30 Aug. 2012
>> 0.3 - 0.2 - 0.1
ans =
-2.7756e-17
The answer is the limited precision of floats. Using the same approach outlined in the FAQ gives:
>> sprintf('%20.18f\n', [.95 .03; .05 .97]-eye(2))
ans =
-0.050000000000000044
0.050000000000000003
0.029999999999999999
-0.030000000000000027
>> sprintf('%20.18f\n', [-.05 .03 .05 -.03])
ans =
-0.050000000000000003
0.029999999999999999
0.050000000000000003
-0.029999999999999999
0 Kommentare
Weitere Antworten (1)
Manoj Kumar
am 9 Mai 2019
What's wrong ?
det(b) = 0 is equivalent to det(b) = 2.7756 x 10^*(-18) =0.
0 Kommentare
Siehe auch
Kategorien
Mehr zu Introduction to Installation and Licensing finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!